/*
 *    Copyright 2009-2023 the original author or authors.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *       https://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */
package com.sheepone.util;

import java.util.AbstractMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Objects;
import java.util.function.Function;

public class MapUtil {
    /**
     * A temporary workaround for Java 8 specific performance issue JDK-8161372 .<br>
     * This class should be removed once we drop Java 8 support.
     *
     * @see <a href=
     * "https://bugs.openjdk.java.net/browse/JDK-8161372">https://bugs.openjdk.java.net/browse/JDK-8161372</a>
     */
    public static <K, V> V computeIfAbsent(Map<K, V> map, K key, Function<K, V> mappingFunction) {
        V value = map.get(key);
        if (value != null) {
            return value;
        }
        return map.computeIfAbsent(key, mappingFunction);
    }

    /**
     * Map.entry(key, value) alternative for Java 8.
     */
    public static <K, V> Entry<K, V> entry(K key, V value) {
        return new AbstractMap.SimpleImmutableEntry<>(key, value);
    }

    public static <K, V> void removeNullValueEntry(Map<K, V> map) {
        map.entrySet().removeIf(entry -> Objects.isNull(entry.getValue()));
    }

    private MapUtil() {
    }
}
